Self-cleaning straining device



Get. 8, 1946. w. R. DODGE 2,408,741

I SELF-CLEANING STRAINING DEVICE v Filed Aug. 11, 1944 .z sneetsrsheet 1 I Ill/61220,":

Oct. 8; 1946. WRDODGE 2,408,741

SELF- CLEANING STRAINING DEVICE Filed Aug. 11, 1944 2 ShetS-ShGet 2 )fllzbmiii Jaye,

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1 wastesl g r M I I To providefimprovements' inconstruction; as- I sembly and action. inorderito attain :efiiciency r I Fig; is"a"plan section Patented Oct. 8, 1946 I I w 1.1-. =.I t. 1 1 in p. 7

sstr cms me STRAINING DIJVICE v I R. Dodge,Aldan,Pagassignor to Hajoca l C rporation, a corporation of Delaware I I i pi' 'Applicatien August 1 '1 clai (01.210-167) My invention relates :to 'mproved method and means for straining fluids and liquids.

The following are among my objects:

To improve the method -of maintaining the strainer unit clean', .wh'ile operatin thereby securing'the maximum of efficiency" 7 To conserve a substanti l bulk offoreign material'which would ordinarily go to waste. r

v :To utilize the pressure of the fluid passing frominlet to discharge :to provide the power necessary for: the cleaning operation; 1 Y 1 To provideia shearing action upon the foreign material adhering'f-to the str'ainer-unit in order to separate smallerrpart's of foreign matter from larger parts, in order to prevent unnecessary and economy as a;whole.. -V .1 #Referring to; the drawings, Which. illustrate merely by way of example, suitable means for et ng invemiQn.-., r.

- Fig. 1 is a} centr a l vertical; section. v

Fig. 2 ,isa .cen

2-2 of Fig.1. 7 t I w Fig. 3.is a fragmentary sectionon a larger Sean V l a.

' F g.1; isia detail in' elevation of itlheshaft' for ""iFigj l is atop 'planview of the helix'g f {the line 5 -5 or Fig."2.: I 5, I Similar numerals referto similar parts throughout the several views. 3 V The device herein described suitably effecting thejinvention, comprises"thechambered body or housing l5 provided atthe top'with an'inlet port "I6 and a discharge'portl'l. This housing is providedwith an inw'a'rdlyiprojecting annular flange l8 nearth'e topand cooperating in forming an intakejspace' fl 9 fonreceivingthe fluid entering at IS. A basket 22hasa"foraminous wall, that is providedwith perforations such wall. This basket is supporte'd at the top by the flange l8. It isalsosuppo -tediat the'bottom by a plug if ormation"24' threaded into the bottom of the housing; 'Q

The basket '22 is cylindrical in form 'open at the top to the intake space l9, and spaced from the surrounding wall of the housing l5.

This space 20, surrounding the fluid delivered throughthe perforations. and delivers the same to the discharge IT.

The housing is adapted to be opened at the top and at the bottom. Suitable closure elements tral vertic l section on the -line I 1, 1944. serial No. 4 ,9 9;

less similar to "constructions are provided for said openings as shown. A hand; to the basket for con-- dle'or bail is see re venience in handling. J

The construction so far described is more or found in the prior art In accordance with my invention a shearing blade in the form of a helix is mounted in the basket on be'ari'ngsat either end; 'This'shear'in'g element is formed into'ahelix mounted upon a rotatable shaft; co-axial withthe basket-the perimeter of the helix having a close movable fit with the inner wall of the basket 7 Y The jphrase"foreign "material? as used "in this case is intended to include any particles or substance in or of "the liquid that will not normally pass through the perforations; 'The plug formation 24 is v a threaded into the open lower end of the housing l5 and serves to close said lower end when in operation,or to'open aid' r for cleaning (blow down) orthe {Mofeparticularly the formation 24 is funnelshapd' as ajt i le provided with an annular flange 2 4 -for receiving the loWer e'n'dj of the basket22.

Below thefunnel-sh'aped formation is a closure "disciz l f'or gaining-access to the housing, Where- 'by the basket may be inserted or withdrawn from the housing. A plug controlled port 24 is provided irf-the losure disc 2 4 forfurther or supplemental control.

v H The top of the housing [5 may also bev opened and closed by means of a cover-plate; cross-bar as 26 in its withdrawing the straining baske and set-screws, in which case asuitable bail 25 maybe used. I his bail 25 is an archformati'on having its 'lower ends secured to the tQ p' Of the basket 22 and furnishesconvenient means for v V basket from the housing and for replacing said basket within said housing.

Thedevice and o eration, so far as above dcaccordance withthe com.-

Among the difficulties encountered" in said theistrainingoperation and results in waste'cf the basket, receives time and material. r 1

Such trouble arises differently indifferent types 'of'material,"and the object of the presentinvenpracticejis the tendency. of the t to gather upon its surface,- a coating eof foreign material, that greatlyimpedes The perimeter of the helix is normally co-aXial with that of the cylindrical basket.

The helix 39 is mounted upon a shaft 32, also coaxial with the basket, by means of a number of radial arms 31 secured to the spindle or shaft 32.

The shaft is mounted in bearingsof cross bars 33 and 34 at the top, and bottomof the basket. These bearings are supported onsuitable crosspieces associated with the housing.

The radial arms 3| are all fixed upon the shaft 32. A washer 35* is slidably mounted on shaft 32 and adapted to rest upon the cross bar 34. .A spring 31 is positioned upon the shaft 32, between the lowermost radial arm 31 and said -bearing in By this arrangement, when the cross bar 34. helix is pushed downwardly the spring :is com.-

pressed; when however the spring is permitted to react, the helix is slightly elevated.

When the shaft 32 is spring-actuated upwardly,; the washer BSlimits thisspring-actuated .up- .Ward movement oftheshaf-t-BZ.

The angle ring is shown insections,inlligs. ,1 and .2, and comprises ;a .strip ;of .metal havin parallel extensions in planes at r ht angles and cooperates with the flanges 18 in the support of the basket.

Inthe usual practice, the mediu tobe strained is introduced throughinlet 16,;1ntoinlet chamber I 9 a d ence into..ibasket.22. From .basketzzthe ul o he med um passesthr ueh th p r ati in the wall ofth as et 22 t t spa e 9 between the basketrandthe :Wall of the housing [5 and thence to theoutlet or discharge port I'l.

If the, medium containsparticles of foreignmarial in appr ci ble Qua tity t a ill not immediately pass through .theperforations in the basket wall, thesaid materialisheld in suspension in the fluid until a substantialpart of same has passed through the perforations.

,Such common practice has a number of objections. For example-the foreign material which is separated from thebody of the medium has a tendency to adhere -totthe inner surface of the basket wall. 'Ihis;interfere s=with the straining,

operation. This trouble increases as the accumulation on the basket wall increases; thus requiring'frequent cleaning of .thebasket which is ex- ,pensiveandwasteful.

The means and method in accordance with my invention serve to overcome the above cited objections H The bearings in cross bars 33 and 34 are sufficiently loose to permit not only vertical and rotative movement but alsoslightrocking or side- 1,

way motion for the purpose to be described. In certain cases it may be desirable to provide-ball bearings. The-helix may be made of sheetmetal or cast and may varyin-gaugeas circumstances require.

The operation employing, the helix is as follows: The medium flowing into the top of th,e"bask.et 22, will directly enco'unterthe helix blade. and, due to the differential pressure or flowfrominlet IE .to outlet l1, will cause the rotation of said helix. Meanwhile part of the -medium will pass out through the perforations 26 into the space 20 within the housing.

,In accordance with the method and means of the present invention, these objectionsare largely .overcome. For example:

ing space 20. In this way material is saved and thetimezrequired in frequent cleaning also saved.

As the rotation of the helix is continuous it fol- -'lows that thereis-no time for undesirable accumulation-of particles.

. -When -the;partof the foreign material which projects into the basket is sheared from the part lodged'in said perforation there is nothing to hold the balance of said foreign matter from passing into the .filtered liquid :zpassing :through the housing. if

When: a up article; of z-foreign zmaterial, happens :ztO be,.cf. .such;cha1tacter1asuto render it .difiioult to -di Qlge :from a1znerforation, the difficulty, cantbe largely overcomerby'gthe. mounting ,of;the; helix.

Animpertant :fe ture :of :the invention is; that when .the 'rnrass ;of medium projecting into the baske issheared. the sa nagqesinto andibecomes "part of .-th;e-m 1strainie;d:medi ni :in the basket,

while the balance of ,saidxnhSs medium. remain- :ineih he peri ratinn willgoiintothe (strained nedi .u-iir uns -u asaid asket. V Thi operation lay bezrep atedzfmm time .1110

time. the :s idma-ss of: unstre ned medium may be reduced or even eliminated. This will igesnlt in savin ;ofitimetanmmaterial, fl'llntcissto say, the, mass may be gradually Worn; away, or .sufiiciently reduced, to permitiitsr passing through'the perforationfand become :part of the strained medium. l 1 I It will also be notedthattherotation ofthe helical blade-withinthebasket-will"increase the agitation oft hefluid passing therethroll h which will facilitate the straining action? What I claim is: j'

In a filtering device, thehombination of acasing'ope'n at the top andbottom'andprovided at its upper portion with .an annular, lateral, v-inwardly projeotingefiangaa hollow .plug member 'closing the lower end of'the casing and provided with anupwardly extendinginverted conical'portion and having an outlet for. 'so'1ids.,.a perforated open ended cylindrical basket arranged ,within the casingandspaced from. the .walls thereof and ,seated'upon saidoonical portion having its. upper end arranged within the annulusdefined'bysaid inw dly pr je tin flan e, .cress bars p vided with bear fig an located in said. conical portion andin the toppfthe baskeaja shaft journaledjin .said bearings, gahe'lic'al .blade mounted on said shaft in close proximity .to ,said basket for .rota- .ti'on and for .shearingmaterial projecting from ,theinter-ior.ofth'lbasket .wall, aninlet in line with .the uppenopen end of ,thebasket and. an outlet located at the top of the casing ,andcommunicating with the space between the .casing and the basket.

' 2R. .DQDGE. 

